Method of and apparatus for burning fuel



Nav. 26, 1940. E. G. BAILEY METHOD OF AND APPARATUS FOR BURNING FUEL Filed June 24, 1936 2 Sheets-Sheet 1 INVENTOR .EF1/n G. Bailey 1&5? kmr TTORNEY Nav.26, 1940. E. G. BAILEY METHOD OF AND APPARATUS FOR BURNING FUEL 2 sheets-sheet 2 Filed June 24, 1936 Patented Nov. 26,

arvlndnaueansmaramdnwumnsbcock&WllcoxCompf.ny,Newark.N.J.,aoor

poration of New Jersey Application June 24, 1938, Serial N0. 80,9

My present invention relates in general to methode of and apparatus for burning solid fuel. More particularly, my invention is concerned with an improved method of and apparatus for 6 burnin( solid fuel, such as bituminous coal and analoaous grades and kinds of solid fuel.

The general types of apparatus now in use for burning* solid fuel are notl free from objectionable characteristics. Mechanical stoken are 1l() dimclllt t0 control t0 maintain desirable fuel burnin: conditions, sensitive to any variation in the character of the fuel supplied. and'not -well adapted for small capacity installations such as is required for domestic service. While -ll Dulverised fuel ilrina has been found 'senerally satisfactory for medium and larae sise furnaces, the pulverilation is an item of considerable expenae.anddimculties arlseinremovins ash from .90 slalonihefurnacewalls andheat transfer surface. and froml the presence of fly ash inthe products of combustion. Moreover, a larger furnace volume is usually required for the zeneration of a given 'amount of heat with pulver- `l mamsnnnnmwltnwmuormeemmen In accordance with my present invention solid the combuationchamher. Inmyimprovedproc- Us of burning solidvfuel. theV fuel is introduced,

'gmfmmymemmeaiormormranmto awroximately a half inch maximum. into one endofafuelcompreesion and combustion chamtubularmasswhichisprosressivelymovedto s am manchem ena at the chamber. mr for "-Vftlsefueltollodiachai'leiiiliamoltenconnlli- (Cl. 11C-1M) tion. Thecombustionchamberisarransedto discharge the hiah temperature heating gases into an associated heat utilizing device.

The various features of novelty which characterine'my invention are pointed out with parll ticularity in the Vclaims annexed to and forminar a part of this specification. For a `better understanding of the invention, its operating advantages and specific objects attained by its use, reference should be had to the aooompany- '.10 ins drawings and descriptive matter in which I have illustrated and described a preferred cui bodiment of my invention.

Of the drawings: y

Fix. l 'is a-.sectional elevation of one form. of fuel burner constructed in accordance with my invention. the plunler operatinz mechanism being omitted;

Fig. zisanenlarsed endviewoftheapparatus ahowninl'iz. 1; f Y im Flg.8isapianvlewpartlyinsectlonofthe apparatus shown in Pis. l, the hopper heinz omlttodf Fig. 4 isadiazrmmxnaticvviewoftliezfuely the end of its compression stroke; and

Fimisssimilarviewwiththefuelcompression means atthe beginning o! its compression stroke.

chamber with the fuel compression menaient-g5` mmmwiwlnsvemuamsaonermfm ofsuitableapparatusfcu'carryinaoutmyimchargethroushalmrnerportI8fl'medillfmV wall il of anlalociated heat utilisinz'device. Themember lliapreferably ofcircularcronn section, asshownfalthou'sh other crow-sectional shapesmaybeusedThetubularmsmberll-m `isprovideiion'itsperiphles'yxvliahahclical111x445 il, which unites wlththe member-and anouter tubular member il toformahellcal pesage I1 for a coolinl duid 'extendida lsubstantially the full lensth of themember Il. the outer end and arranaedaxiallyof the tu-fso' or more spiral vanes 24 are positioned in the pipe I3 adjacent its inner or discharge end. An' air supply connection 2| opens to the inner end of the helical passage I1 In the outer end of the tubular member I0 is positioned an annular plunger 22 surrounding the air pipe I3 and movable in the member III from the outer end of the fuel supply passage II inwardly a predetermined distance. The outer end of the member I0 has its upper half cut away and its lower halfy provided with diametrically opposite horizontal flanges 23, which slidably support reciprocating arms 24 extending laterally from the plunger 22.

The mechanism for actuating the arms 24 and thereby the plunger 22 comprises a pair of hydraulic cylinders 25 arranged at opposite sides of the tubular member I 0, each cylinder containing a piston 25 mounted on a piston rod 21, which extends through the outer end wall of the cylinder and has its outer end connected to the corresponding arm 24. The mechanism for actuating and controlling the operation of the pistons 23 includes a water supply pipe 30 having a c'ontrol valve 3i therein and leading to one side of a four-way control valve 32, to the opposite side of which a drain pipe 33 is connected. Pipe lines 3d and 3are connected to the remaining opposite'sides of the valve 32. the pipe line 34 being connected to a pipe' 38 leading to the outer ends of the cylinders 25 through branches 3l and 33. In the branch 33 is located an adjustable needle valve 39, while the,branch 31 is provided With a check valve 40 arranged to permit a fluid flow only from the pipe 36. 'I'he pipe 35 divides into lequal branches 4I, the ends oi which are connected to the inner ends of the cylinders 25. The valve 32 maybe advantageously connected to suitable automatic valve operating mechanism (not shown) which may be adjusted along with the valve 39 to obtain any desired speed of the plunger 22.

With the pistons 25 in the outer ends of the cylinders, the valve 32 is set so that water from the pipe 3U enters the pipe 34 from which it passes into the branch 38, through the needle valve 33' and into the cross pipe 36 through which it enters the outer ends of the cylinders. At the same time water is entering behind the pistons 2B any fluid in front of the pistons passes out through the branch pipes 4I into the pipe 35 and through the valve 32 to the drain connection 33. As the vpistons complete their forward strokes, the valve 32 is shifted to disconnect the pipe 35 from the drain 33 and connect it to the supply pipe 30. This change in the position of the valve 32 closes the connection between the pipes 33 and 34 and connects the latterI to the drain 33. Water then enters the inner ends of I3 and tubular member the cylinders 25, and any water present lbehind the pistons 23 passes through the branches of the pipe 36 te the pipe 31 and through the check valve 40 to the pipe 34 and drain 33. With the foregoing operations, the pistons 25 will have a slow forward stroke and a relatively fast return.

In normal operation with the apparatus described, solid fuel is supplied to the hopper I2, preferably in a crushed condition, and delivered from the hopper to the tubular member I0 through the port II during the return stroke of the plunger 22. During each inward or compression stroke of the plunger, a fuel charge is compressed in the annular space between the Lair pipe I0. During the compression stroke of the plunger 22 an inward movement of the previously compacted fuel mass 5l is also effected in the tubular member III. A swirling stream of preheated air is discharged from the pipe I8 axially of the compacted tubular mass of fuel and effectively scrubs the exposed 5 inner surface of the fuel mass. Ignition of the fuel is effected in any suitable manner and combustion will continue at a relatively high rate of heat release in the inner portion of the tubular member I0. The radiant and conducted heat from the burning fuel in the inner section of the member I0 gradually raises the temperature of the fuel as it approaches the combustion zone, causing the moisture and volatile combustible gases to be driven off, and coking the fuel. The 15 coking of the fuel mass causes it to swell and become initially tarry and then dry and the straight form of the member I0 causes the fuel massto resist but not prevent movement and hold its shape against disintegration after passing beyond the inner end of the air pipe I8- until lt has burned away from the inside by the flow of air therethrough. Y

When the apparatus is ilrst put into use, the fuel can be compacted in position around the air 25 pipe I8 by any isuitable means for ignition and initial coking. After the apparatus has once been used, a coked tube of fuel, as shown in Fig. 5. will be present in the member III and can be directly ignited in any known way. 30

The cross-sectional area and length of the tubular 'member I0, the size of the air pipe I3 and the air and fuel supplies are so relatively proportioned that combustion will be completed before the fuel mass can reach the member I0. As shown in Figs. 4 and 5, the inner exposed surface of the fuel mass assumes the shape of a flaringzone extending from substantially the inner end of the air pipe to the inner end of the member III. 'Ihe speed of the 40 plunger 22 is advantageously regulated in accordance with the rate of consumption of the tubular fuel mass. When the` plunger reaches the end of its compression stroke the inner end of the fuel mass will be at approximately the inner end of the member I0, as shown in Fig. 4. During this stroke of the plunger the portion of the fuel mass immediately beyond the inner end of the air pipe tends to expand slightly toward the axis of the chamber, according to the well known so pressure conditions found in coking apparatus, as indicated at 5I. As the stream of air continues and combustion proceeds, the bulging portion will be rapidly burned away and the inner portion of the fuel mass will acquire the shape shown in Fig. 5. The fuel when coked has a strong structural formation which facilitates longitudinal movement of the portion of the fuel mass located beyond the inner end of the air pipe by the plunger movement.

'Ihe stream of air for combustion is regulated to scrub the surface of the burning fuel at a sufficiently high velocity to maintain a high rate of combustion per unit of exposed fuel area, and to burn substantially all of the combustible gases evolved in the combustion chamber. The scrubhing action of the air on thefuel surface is facilitated by the whirling movement effected by the vane 20. The rateof combustion is readily controlled by varying the rate of air discharge from the pipe I3. The rate of fuel supply may be Separately controlled by varying the speed and number of strokes of. the plunger 22. 'I'he normal heat release rate maintained will be sufficient to maintain the temperature in the combustion the inner end of 35,

zone above the fusion temperature of the ash in the fuel and the ash will fuse into molten particles in the combustion chamber. With the axis of the burner arranged horizontally, as shown,

5 the molten particles of ash will be carried out of the inner end of the combustion chamber by gravity and the dragging effect of the products of combustion, and drop into the bottom of the associated heat utilizing device, while the products of combustion will be utilized for heat transburner.

The fuel burning method and apparatus described are particularly effective for burning solid fuel in a relatively small combustion space, while disposing of the ash content in a manner which n will render the products of combustion free from cinders and fly ash. l

While in accordance with the provisions of the statutes I have illustrated and described herein the best form of my invention now known to 3| me. those skilled in the art will understand that many changes may be made in the particular form of apparatus disclosed without departing from the spirit of my invention as covered by the claims, and that certain features of my n method and apparatus may sometimes `be used to advantage without a corresponding use of other features.

I claim:

l. A method of burning solid coking fuel which al comprises introducing the fuel into one end of a chamber, compressing the fuel introduced into a tubular mass in the chamber, igniting the tubular mass of fuel, maintaining a stream of air for combustion axially of and scrubbing the exposed inner surface of said burning tubular mass, discharging the heating gases generated from the opposite end of the chamber, and advancing the tubular mass of fuel towards said opposite end of the chamber.

2. A method of burning solid coking fuel which comprises introducing the fuel into one end of an elongated chamber, compressing the fuel introduced into an elongated tubular mass in the chamber, igniting the tubular mass of fuel, main`- taining a stream of air for combustion axially of and scrubbing the exposed inner surface of said burning tubular mass and at a velocity sufficient to maintain a high rate of combustion per unit of exposed fuel area and burn substantially all u of the combustion gases evolved, discharging the heating gases generated from the opposite end of the chamber, and advancing the tubular mass of fuel towards said opposite end of the chamber.

3. A method of burning solid coking fuel which comprises introducing the fuel into one end of an elongated chamber, compressing the fuel introduced into an elongated tubular mass in the chamber, igniting the tubular mass of fuel, maintaining a stream of air for combustion axially of and scrubbing the exposed inner surface of said burning tubular mass and at a velocity sumcient to maintain a high rate of combustion per unit of exposed fuel area and burn substantially all of the combustible gases evolved, discharg- 70 ing the heating gases generated from the opposite end of the chamber, and progressively advancing the tubular mass of fuel towards the discharge end of the chamber.

4. A method of burning solid coking fuel which 5 comprises periodically introducing the fuel into one end of an elongated chamber, compressing the fuel introduced into an elongated tubular mass in the chamber, igniting the tubular mass of fuel, maintaining a stream of air for combustion axially of and scrubbing the exposed inner 5 surface of said burning tubular mass and at a velocity sumcient to maintain a high rate of combustion per unit of exposed fuel area and burn substantially all of the combustible gases evolved.

discharging the heating gases generated from 410 the opposite end of the chamber, and periodically advancing the tubular mass of fuel towards the discharge end of the chamber.

5. A method of burning'solid coking fuel which comprises introducing the fuel in a finely divided l5 form into one end of an elongated chamber, compressing the fuel introduced into an elongated tubular mass in the chamber, igniting the tubular mass of fuel, maintaining a swirling .stream of preheated air for combustion axially of andb scrubbing the exposed inner surface of said burning tubular mass and at a velocity sufficient to maintain a high rate of combustion per unit-of exposed fuel area and burn substantially all of the combustible gases evolved, advancing the tu-`- bular mass of fuel towards the opposite end of the chamber, and discharging the heating gases generated from said opposite end of lthe chamber and utilizing the heating gases for heat transfer purposes'.

6. Apparatus for -burning solid fuel comprising means forming a fuel compression and combustion chamber, means for supplying solid fuel to said chamber, means in said chamber for com- 85 pressing the fuel supplied thereto into a tubular mass, and means for introducing a stream of. air for combustion axially of and scrubbing the exposed inner surface of said tubular mass.

7. Apparatus for burning solid fuel comprising means forming an elongated fuel compression 4 and combustion chamber, means for supplying solid fuel to one end of said chamber, means in said chamber for compressing the fuel supplied thereto into an elongated tubular mass and advancing previously compacted fuel towards the opposite end of said chamber, and means for introducing a stream of air for combustion axiallyv of and scrubbing the exposed inner surface of said tubular mass and at a velocity sufficient to maintain a high rate of combustion per unit of exposed fuel area and burn substantially all of the combustible gases evolved.

8. Apparatus for burning solid fuel comprising means forming an elongated fuel compression and combustion chamber, means for supplying solid fuel in a finely divided condition to one end of said chamber, means in said chamber for compressing the fuel supplied thereto into an elongated tubular mass and advancing previously compacted fuel towards the opposite end of said 00 and combustion chamber, means for supplying 70 solid fuel in a finely divided condition to one end of said chamber, means in said chamber for cornpressing the fuel supplied thereto into an elongated tubular mass and advancing previously compacted fuel towards the opposite end of said 15 exposed f chamber, means for introducing a swirling stream of preheated air for combustion axially of and scrubbing the` exposed inner surface of said tubular mass and at a velocity sufficient to maintain a high rate of combustion per unit of exposed fuel area and burn substantially all of the combustible gases evolved, and heat uti lizing apparatus arranged to receive heating gases from the opposite end ofsaid chamber.

10. A fuel burner comprising a tubular member having a fuel supply opening adjacent one end and open at its other end for the discharge of heating gases, means for supplying solid fuel to said fuel supply Opening, a combustion air supply pipe axially arranged in said tubular member at said one end thereof, a plunger surrounding said air pipe and movable in said tubular member between said one end thereof and the discharge end of said air pipe, and means for reciprocating said plunger in said tubular member to compress fuel entering said fuel supply opening into a tubular mass.

1i. A fuel burner comprising an elongated tubular member having a fuel supply opening adjacent one end and open at its other end for the discharge of heating gases, means for sur Plying solid fuel to said fuel supply opening, a combustion air supply pipe axially arranged in said tubular member at said one end thereof, an annular plunger surrounding said air pipe and movable in said tubular member between said one end thereof and the discharge` end of said air pipe, and means for reciprocating said plunger in said tubular member to compress fuel entering said fuel supply opening into a tubular mass and advance previously compacted fuel tcwards said other end of said tubular member.

' i2. A fuel burner comprising an elongated ganarse tubular member of heaty resistant material having a fuel supply opening adjacent one end and open at its other end for the dischargeof heating gases, means for supplying solid fuel in a finely divided condition to said fuel supply opening, a combustion air supply pipe axially arranged in said tubular member at said one end thereof, an annular plunger surrounding said air pipe and movable in said tubular member between said one end thereof and the discharge end of said air pipe, means for reciprocating said plunger in said tubular member to compress fuel entering said fuel supply opening into a tubular mass .and advance previously compacted fuel towards said other end of said tubular member, a cooling jacket surrounding said tubular member, and means for passing air through said* cooling Jacket and delivering the preheated air to said air pipe.

i3. A method of burning solid coking fuel which comprises compressing the fuel into a tubular mass, igni-tlng the mass of fuel, while maintaining a supply of air thereto and continuing to pass a stream of air for combustion axially of and scrubbing the exposed inner surface of said burning tubular mass. and moving the tubular mass of fuel towards the combustion zone as combustion proceeds.

14. A method of burning solid ycoking fuel which comprises compressing the fuel into a tubular form in a combustion chamber while advancing a tubular mass' of previously compacted burning fuel in said chamber, and passing a stream of air for combustion axially of and scrubbing the exposed inner surface of said tubu- 1&1 mass.

ERVIN G. BAILEY. 

